The vacuum pump or the drive motor is
blocked
Make sure the drive motor is disconnected
from the power supply
Remove the fan cover
Try to turn the drive motor with the vacuum
pump by hand
If the vacuum pump is blocked:
Repair the vacuum pump (Busch service)
The drive motor is defective
Replace the drive motor (Busch service)
The vacuum pump is blocked
Solid foreign matter has entered the vacuum
pump
Repair the vacuum pump (Busch service)
Make sure the suction line is equipped with a
screen
If necessary additionally provide a filter
Corrosion in the vacuum pump from remain-
ing condensate
Repair the vacuum pump (Busch service)
Check the process
Corrosion between the rotor (h) and the hous-
ing (g)
Eliminate by use of anti-rust liquid
Ice in the vacuum pump
The operating liquid is congealed
Carefully warm up the vacuum pump
Defrost the operating liquid
The vacuum pump was run in the wrong di-
rection
Repair the vacuum pump (Busch service)
When connecting the vacuum pump make
sure the vacuum pump will run in the correct
direction (
Ú
page 8: Installation)
The drive motor is running, but the vacuum
pump stands still
The coupling between the drive motor and
the vacuum pump is defective
Replace the coupling element
The vacuum pump starts, but labours or runs
noisily or rattles
The drive motor draws a too high current
(compare with initial value after commission-
ing)
Loose connection(s) in the drive motor termi-
nal box
Not all drive motor coils are properly con-
nected
The drive motor operates on two phases only
Check the proper connection of the wires
against the connection diagram
Tighten or replace loose connections
The operating liquid level is too high
Adjust the regulating valves
Density or viscosity of the operating liquid too
high
The performance data is based on water
(1000 kg/m³, 1 mm²/s), higher density or vis-
cosity require higher shaft power
Provide a different operating liquid or a stron-
ger drive motor
Friction between the rotor and the front of the
housing
Disassemble the vacuum pump, clean it and
adjust to proper clearances
The vacuum pump runs in the wrong direction
Verification and rectification
Ú
page 5: Instal-
lation and Commissioning
Foreign objects in the vacuum pump
Stuck bearings
Repair the vacuum pump (Busch service)
The vacuum pump runs very noisily
Defective bearings
Repair the vacuum pump (Busch service)
The vacuum pump cavitates (periodic forma-
tion and collapsing of steam bubbles in the
operating liquid;
Ú
page 5: Installation and
Commissioning)
Increase the working pressure (vacuum relief
valve) or decrease the temperature of the op-
erating liquid
In case of suction of condensable vapours:
make sure that enough non condensable gas
is conveyed along
CAUTION: continuous operation under cavi-
tation will destroy the vacuum pump
Worn coupling element
Replace the coupling element
LA 0053-1111 A, LB 0063-1011 A
Troubleshooting
0870150638 / 091222
page 14
Summary of Contents for DOLPHIN LA 0053-0143 A
Page 27: ......
